- Choose length = 1 m,
damping = 1 sec-1, and
amplitude = 0.2 m
(this are the default settings when the applet is started). Now, change the
frequency of driving very slowly from 0.2 Hz to
0.8 Hz. Observe the change in the amplitude of oscillation and the change
in the phase between driving and pendulum oscillations.
You can measure it by using the oscilloscope.
| Related topics in the lecture room:
Resonance.
|
- Choose length = 1 m,
damping = 0.1 sec-1,
amplitude = 0.07 m, and
frequency = 1.2 Hz. Slowly decrease the frequency down to
0.2 Hz and observe (and measure) the amplitude of oscillation. You should find
two regimes of strong oscillations (resonances). In order to distinguish both regimes,
compare the oscillation frequency with the driving frequency.
- Choose length = 1 m,
damping = 0.1 sec-1,
amplitude = 0.07 m, and frequency = 0.44 Hz.
Depending on the initial condition, you will get either a strong or a weak oscillation.
- Choose length = 1 m,
damping = 0.1 sec-1,
amplitude = 0.07 m, and frequency = 0.8 Hz.
Depending on the initial condition, you will get either a strong or a weak oscillation.
- Choose length = 1 m,
damping = 1 sec-1, and
frequency = 0.7 Hz,. Slowly increase the amplitude of driving
from 0.3 m to 1.8 m and observe the increase and decrease of
complexity in the motion of the pendulum. For example, you will get period-doubling
bifurcation between 0.35 m and 0.36 m,
chaos at 0.4 m and 0.85 m,
a period-4 orbit at 0.8 m,
and bistability between 1.45 m and 1.7 m.
|
elmer@ubaclu.unibas.ch
last modified Wednesday, July 29, 1998.
